Amino Acid Sequences of Lactoferrin from Red Deer (Cervus elaphus) Milk and Antimicrobial Activity of Its Derived Peptides Lactoferricin and Lactoferrampin

Abstract

Although the bioactivities of bovine lactoferrin have been extensively investigated, little is known about deer milk lactoferrin bioactivity and its amino acid sequence. This research investigated the amino acid sequence of deer lactoferrin and the antimicrobial activities of two lactoferrin-encrypted peptides; lactoferricin (Lfcin) and lactoferrampin (Lfampin). Deer lactoferrin was found to have a molecular weight of 77.1 kDa and an isoelectric point of 7.99, which are similar to that of bovine lactoferrin, 78 kDa and pI 7.9. Deer lactoferrin contains 707 amino acids, one amino acid less than bovine lactoferrin, and has 92% homology with bovine lactoferrin. Deer lactoferricin exhibited strong antimicrobial activity against E. coli American Type Culture Collection (ATCC) 25922 and L. acidophilus ATCC 4356. The antimicrobial activities of deer and bovine Lfcin and Lfampin were compared. Based on MIC, deer Lfcin was found to be a more effective inhibitor of L. acidophilus ATCC 4356 than bovine Lfcin, but bovine Lfcin and Lfampin were more effective against E. coli ATCC 25922 than deer Lfcin and Lfampin. The deer Lfcin sequence differed at seven amino acids from bovine Lfcin and this decreased the net positive charge and increased the hydrophobicity. Deer Lfampin contained two differences in amino acid sequence compared to bovine Lfampin which decreased the net positive charge. These amino acid sequence differences likely account for differences in antibacterial activity. Positive charge and hydrophobic residues provide the amphipathic character of these helical peptides, and are considered important for binding of antimicrobial peptides. In silico modelling of deer Lfcin indicated an identical α-helical structure compared to bovine Lfcin.

Research Advances of Lactoferrin in Electrostatic Spinning, Nano Self-Assembly, and Immune and Gut Microbiota Regulation

“…Studies compared the structure of human LF with that of human serum transferrin; human milk proteins are linked to poly nacetyl-lactosaminoglycans at each valve, whereas bovine milk proteins contain α-1,3-linked galactose molecules at the terminal nonreducing position, and these glycans increase the stability of milk proteins to proteases and acidic pH. 3 Of course, structural features such as LF amino acid sequences have been discovered in a variety of species, including Cervus elaphus, 24 mice, 25 camel, 26 sheep, and goat. 26 Serum transferrin and ovotransferrin are the other two members of the transferrin family.…”

Non-Bovine Milk: Sources and Future Prospects

“…Deer, donkey, and mare milk are not widely consumed or traded, but they have significant cultural importance in certain communities [2]. Recently, non-bovine milk has been the focus of extensive research activities due to its potential health benefits, as summarized in recent reviews [3][4][5][6], and due to interest in incorporating these types of milk in infant formula [7,8] because of their low allergenicity compared to cow milk.…”

“…The high solid contents of sheep, buffalo, and deer milk, especially the protein content, result in different physicochemical properties compared with cow milk (e.g., highest viscosity and micelle mineralization) and can result in a higher cheese yield and higher nutrient density. In particular, interesting properties such as hypo-allergenicity and immunomodulatory activities [3,13,14] have been a catalyst for ongoing research activities.…”

Synergistic Antimicrobial Action of Lactoferrin-Derived Peptides and Quorum Quenching Enzymes

“…Lactoferrin itself is a serum iron-binding protein belonging to the transferrin family and is one of the most well-studied milk proteins exhibiting high antimicrobial, antiviral, anti-inflammatory, antioxidant and anti-cancer activities [ 11 ]. Lactoferrin is produced by epithelial cells of various organs and presents in most secretory fluids (0.001–6 g/L), including colostrum, milk, saliva, bile (including gastric and intestinal juice), urine and vaginal fluid [ 12 ]. As a result of careful studies conducted over many years of mainly antimicrobial properties and the mechanism of action of lactoferrin isolated from various sources (human, cow, buffalo, deer, ship, mouse etc.)…”